Experimental and Numerical Investigation of Beach Slope Effects on the Hydrodynamic Loading of Tsunami-like Surges on a Vertical Wall

Abstract

Over the past decades, hydraulic surge generated by dam-break waves has been used to simulate the effects of tsunamis on coastal infrastructure. This study investigates the slope effects on hydrodynamic loading of dam-break waves on structure when propagating over four different inclined beds (0-, 5-, 10-, 15-degree) by experiment and numerical simulation using OpenFOAM and DualSPHysics. Except for small discrepancies in the pressure time-history, numerical results obtained with both OpenFOAM and DualSPHysics agreed closely with the experimental dynamic pressures. The results revealed that the hydrodynamic pressure decreased after an initial impact peak from the lowest transducers in the 5-, 10-, and 15-degree cases when compared with the horizontal case. However, the dynamic pressure of transducers at same corresponding level increased with an increase in the slope. The integrated experimental hydrodynamic forces were similar to the numerical results for the 0- and 5-degree cases, while they were higher for the 10- and 15-degree cases due to insufficient pressure data. By investigating the relation between the force decrease and slopes, a non-dimensional reduction factor was proposed from the linear fitness for slope effects estimation. This experimental and numerical study can provide novel insight on the hydrodynamic force calculation of tsunami-like surges on coastal infrastructures when considering beach slope.